Buggy code:
public strictfp class ExtensionManager implements org . nlogo . api . ExtensionManager { private final Map < String , ExtensionManager . JarContainer > jars = new HashMap < String , ExtensionManager . JarContainer > ( ) ; private final AbstractWorkspace workspace ; private int jarsLoaded = 0 ; public AbstractWorkspace workspace ( ) { } public boolean profilingEnabled ( ) { } public ExtensionManager ( AbstractWorkspace workspace ) { } public boolean anyExtensionsLoaded ( ) { } public String getSource ( String filename ) throws IOException { } public File getFile ( String path ) throws ExtensionException { } private Object obj = null ; public void storeObject ( Object obj ) { } public Object retrieveObject ( ) { } private String identifierToJar ( String id ) { } public void importExtension ( String extName , ErrorSource errors ) throws CompilerException { } public void addToLibraryPath ( Object classManager , String directory ) { } public String resolvePath ( String path ) { } public String resolvePathAsURL ( String path ) { URL jarURL ; try { jarURL = new URL ( path ) ; return jarURL . toString ( ) ; } catch ( MalformedURLException ex ) { Exceptions . ignore ( ex ) ; } <START_BUG> if ( ( path . indexOf ( '//' ) ) > ( - 1 ) ) { <END_BUG> try { java . io . File jarFile = new java . io . File ( workspace . attachModelDir ( path ) ) ; if ( jarFile . exists ( ) ) { return ExtensionManager . toURL ( jarFile ) . toString ( ) ; } } catch ( MalformedURLException ex ) { Exceptions . ignore ( ex ) ; } } try { java . io . File jarFile = new java . io . File ( workspace . attachModelDir ( path ) ) ; if ( jarFile . exists ( ) ) { return ExtensionManager . toURL ( jarFile ) . toString ( ) ; } } catch ( MalformedURLException ex ) { Exceptions . ignore ( ex ) ; } try { java . io . File jarFile = new java . io . File ( ( ( "extensions" + ( java . io . File . separator ) ) + path ) ) ; if ( jarFile . exists ( ) ) { return ExtensionManager . toURL ( jarFile ) . toString ( ) ; } } catch ( MalformedURLException ex ) { Exceptions . ignore ( ex ) ; } throw new IllegalStateException ( ( "Can't<seq2seq4repair_space>find<seq2seq4repair_space>extension<seq2seq4repair_space>" + path ) ) ; } public String getFullPath ( String path ) throws ExtensionException { } private URLClassLoader getClassLoader ( String jarPath , ErrorSource errors , ClassLoader parentLoader ) throws CompilerException { } private ClassManager getClassManager ( String jarPath , URLClassLoader myClassLoader , ErrorSource errors ) throws CompilerException { } private String getClassManagerName ( String jarPath , ErrorSource errors ) throws IOException , CompilerException { } private String getExtensionName ( String jarPath , ErrorSource errors ) throws CompilerException { } public Object readFromString ( String source ) throws CompilerException { } public void clearAll ( ) { } public ExtensionObject readExtensionObject ( String extName , String typeName , String value ) throws CompilerException { } public Primitive replaceIdentifier ( String name ) { } public String dumpExtensions ( ) { } public List < String > getJarPaths ( ) { } public List < String > getExtensionNames ( ) { } public String dumpExtensionPrimitives ( ) { } public void reset ( ) { } List < URL > getAdditionalJars ( java . io . File folder ) { } public void startFullCompilation ( ) { } public void finishFullCompilation ( ) { } private boolean checkVersion ( Attributes attr ) { } private long getModified ( String jarPath , ErrorSource errors ) throws CompilerException { } public void exportWorld ( PrintWriter writer ) { } public void importExtensionData ( String name , List < String [ ] > data , ImportErrorHandler handler ) throws ExtensionException { } public boolean isExtensionName ( String name ) { } private ExtensionManager . JarContainer getJarContainerByIdentifier ( String identifier ) { } private class JarContainer { public final String extensionName ; public final String jarName ; public URLClassLoader jarClassLoader ; public final long modified ; public ExtensionPrimitiveManager primManager ; public ClassManager classManager ; public boolean loaded ; public boolean live ; public String prefix ; JarContainer ( String extensionName , String jarName , URLClassLoader jarClassLoader , long modified ) { } } @ SuppressWarnings ( "deprecation" ) private static URL toURL ( java . io . File file ) throws MalformedURLException { } }

Fix:
if ( path . contains ( java . io . File . separator ) ) {